Which of the following is an example of an imperative sentence

a. that is absolutely ridiculous!
b. what time will stephanie want to leave?
c. remember to get the dry cleaning.
d. shannon has finished all of her homework

First of all, an imperative sentence is always going to perform the action of giving a command or an order.  In this case, the imperative sentence is going to be: C. Please remember to get the dry cleaning.  If you were to add you to the beginning of the sentence, as if the order was directed at you, you could easily come to the conclusion that the sentence is imperative.  Hope this helps.